The hepatocellular carcinoma is one of epithelial malignant tumors developed as a primary carcinoma in a liver and formed of tumor cells similar to hepatocytes. In general, a large number of tumors are formed in a liver and are likely to grow and progress in a hepatic vessel, and a tumor thrombosis is frequently formed in a portal vein. The hepatocellular carcinoma often breaks out in the Asian region including Japan and the African region, and cirrhosis concurs in many cases.
As a marker for detecting hepatocellular carcinoma, use is made have been conventionally of α-fetoprotein (AFP) and PIVKA-II (see Non-patent Document 1), KM-2 (see Non-patent Document 2), CA125 (see Non-patent Document 3), and the like.
Meanwhile, it is known that a post-translational modified, in particular, phosphorylated protein reflects conditions of various organs and tissues. For example, a phosphorylated troponin 1 protein for recognizing a condition of a muscle tissue that has suffered damage (see Patent Document 1); and phosphorylated urokinase to be used for detecting various types of carcinoma (see Patent Document 2).    [Non-patent Document 1] Liebman H A, Furie B C, Tong M J, Blanchard R A, Lo K J, Lee S D, Coleman M S, and Furie B., New Engl. J. Med. 310, pp. 1427-1431. (1984)    [Non-patent Document 2] Kumagai Y, Chiba J, Sata T, Ohtaki S, and Mitamura K. Cancer Res. 52, pp 4987-4994. (1992)    [Non-patent Document 3] Elias J, Kew M C. Int. J. Cancer. 46, pp 805-807. (1990)    [Patent Document 1] JP-A-2006-502203, Title of the Invention “ISOLATED POST-TRANSLATIONALLY MODIFIED PROTEINS FOR MONITORING AND DIAGNOSING MUSCLE DAMAGE”    [Patent Document 2] JP-B-3129430, Title of the Invention “METHOD FOR DETECTING TUMOR DISEASE”